#include <REGX52.H>
#include <intrins.h>
void Delay1ms(unsigned int time)		//@11.0592MHz
{
		unsigned char i, j;
		while(time--)
		{
				_nop_();
				i = 2;
				j = 199;
				do
				{
						while (--j);
				} while (--i);
		}
}

int main()
{
	while(1)
	{
		P2=0x7f;//0111 1111
		Delay1ms(500);
		P2=0xbf;//1011 1111
		Delay1ms(500);
		P2=0xdf;//1101 1111
		Delay1ms(500);
		P2=0xef;//1110 1111
		Delay1ms(500);
		P2=0xf7;//1111 0111
		Delay1ms(500);
		P2=0xfb;//1111 1011
		Delay1ms(500);
		P2=0xfd;//1111 1101
		Delay1ms(500);
		P2=0xfe;//1111 1110
		Delay1ms(500);
		}
		return 0;
}